Complement-mediated dialysis reaction during regular hemodialysis treatment: a case report.

BACKGROUND: Hemodialysis reactions (HDRs) are similar to complement activation-related pseudo allergy (CARPA), a hypersensitivity reaction that occurs when administering certain (nano)drugs intravenously. The pathomechanism of CARPA was described based on animal experiments. Typical CARPA-like dialysis reactions, which occur at the start of hemodialysis, have been reported using polysulfone dialyzers. However, to our knowledge, this is the first dialysis reaction that occurred towards the end of hemodialysis treatment. CASE PRESENTATION: This report describes a 52-year-old Caucasian male patient who had been receiving chronic hemodialysis for 3 years and exhibited a CARPA reaction during his third hour of treatment. Upon activation of the microbubble alarm, the extracorporeal system recirculated for five minutes. Following reconnection, the patient exhibited a drop in systemic blood pressure, chest pain, and dyspnea after five minutes. Symptoms disappeared spontaneously after reducing the speed of the blood pump, placing the patient in a Trendelenburg position, and administering a bolus infusion from the dialysis machine. The remaining dialysis treatment was uneventful. CONCLUSION: Numerous case reports about reactions occurring with modern high-efficiency polysulfone dialyzers have been published. However, due to changes in the material structure by the manufacturers, we have not encountered such cases lately. The recently reported increase in thromboxane-B2 and pulmonary arterial pressure and complement activation upon re-infusion of extracorporeal blood following dialysis may explain the reaction observed here.

Optimal Changes Seen in Patients After Treatment With Poly- l -Lactic Acid: A Retrospective Descriptive Study.

BACKGROUND: Poly- l -lactic acid (PLLA) is a biostimulator that enhances collagen production and leads to volume restoration. It became popular because of its improvement of facial wrinkles and long-lasting effect, although the specific visible changes it causes in the facial area are not fully described. OBJECTIVE: To identify and characterize the visible changes resulting from injecting PLLA into the facial area. METHODS: A list of 678 patients who underwent 2 to 3 treatments with PLLA injections in this center between 2021 and 2022 were retrieved. After 2 rounds of evaluations, 31 independent international evaluators described the 3 main changes they observed in the before-and-after images (taken approximately 7 months after the last injection session) of the 12 patients with the most significant improvement. RESULTS: A total of 1,015 descriptions were received. They were divided into categories based upon similarity. The main detected changes were better contouring and enhancement of the lateral face, a lifting effect and secondary impact on the nasolabial fold, and improvement of skin texture and skin firmness. CONCLUSION: Poly- l -lactic acid injections were judged to be effective for contouring, lifting, and improving skin texture in the facial area. Further research is needed to validate these results and create an assessment scale for PLLA injections.

Consensus recommendations on the use of injectable poly-l-lactic acid in Asian patients.

BACKGROUND: Injectable poly-L-lactic acid (PLLA) has been proven safe and effective with numerous medical applications for more than 25 years. The product has been approved in over 40 countries and is being used for soft tissue augmentation in the face and certain body parts. With the increased demand for subtle and natural-looking aesthetic treatments in the Asia-Pacific region, there is also a heightened need for consistent preparation and effective treatment methodologies to optimize outcomes for Asian patients. METHODS: The body of evidence in medical literature, clinical data of presented case reports, and the collective experience of the authors are reflected in these consensus recommendations, which also take under consideration the availability of biostimulators in the Asia-Pacific region. RESULTS: The resulting consensus recommendations include patient selection and assessment, management of treatment expectations, appropriate preparation and storage, proper injection techniques and treatment plans, management of adverse effects, PLLA combination with other facial rejuvenation procedures, and other constructive considerations. CONCLUSIONS: In the above consensus recommendations, the authors shared their best practices in accordance with the updated preparation and treatment protocols of PLLA. These recommendations represent the clinical and real-world techniques utilized by authors in providing PLLA treatments for Asian patients.

Fragmentation of Hydrophilic Guidewire Coatings During Neuroendovascular Therapy.

PURPOSE: Cerebral polymer coating embolism from intravascular devices may cause serious complications after endovascular therapy (EVT) for neurovascular diseases. Although polymer fragments are often created during endovascular procedures, exact mechanisms of their formation, especially if of small size, are largely unknown. METHODS: In this study eight microguidewires (Asahi Chikai 200 cm (Asahi Intecc, Aichi, Japan), Asahi Chikai Black (Asahi Intecc), Fathom™ (Boston Scientific, Marlborough, MA, USA), Hybrid (Balt Extrusion, Montmorency, France), Radifocus® Guide Wire GT (Terumo, Leuven, Belgium), Synchro2® (Stryker, Kalamazoo, MI, USA), Transend™ EX (Boston Scientific), and Traxcess™ (MicroVention®, Tustin, CA, USA)) frequently used during EVT were investigated ex vivo using their dedicated metal or plastic insertion tools to assess for coating delamination after backloading of the microguidewires. RESULTS: Backloading caused damage to the coating of all microguidewires especially when the main body of the guidewires was bent in front of the insertion tool. All studied microguidewires produced microscopic filamentous and/or band-like coating fragments. Few larger irregular fragments were observed, but also very small fragments measuring 1-3 µm in diameter were found. Spectroscopic measurements of polymer fragments and microguidewires identified various polymers. CONCLUSION: Backloading of polymer-coated microguidewires during EVT should be minimized if possible. More stable hydrophilic coatings on microguidewires and less traumatic insertion tools are desirable.

A Rare Case of Hydrophilic Polymer Embolization After Transcatheter Aortic Valve Replacement.

ABSTRACT: Endovascular procedures that use a hydrophilic polymer-coated device carry a risk of embolization and ischemic complications when used intravascularly. Because these coatings are increasingly used worldwide, it is important to identify potential adverse effects early. Cutaneous complications of hydrophilic polymer emboli are rare and not commonly described in the literature. Therefore, we report a case of hydrophilic polymer embolization with cutaneous findings in a patient who underwent a recent transcatheter aortic valve replacement.

Development of metformin HCl granules using brown flaxseed mucilage as a retardant polymer: effects of polymer and drug ratio

Abstract Flaxseed (Linum usitatissimum L.) is the seed of a multipurpose plant of pharmaceutical interest, as its mucilage can be used as a natural matrix to develop extended-release dosage forms and potentially replace synthetic polymers. In this study, a 3² factorial design with two replicates of the central point was applied to optimize the development of extended-release granules of metformin HCl. The total fiber content of the mucilage as well as the friability and dissolution of the formulations were evaluated. The lyophilized mucilage presented a high total fiber content (42.63%), which suggests a high efficiency extraction process. Higher concentrations of the mucilage and metformin HCl yielded less friable granules. In addition, lower concentrations of metformin HCl and higher concentrations of the mucilage resulted in slower drug release during the dissolution assays. The release kinetics for most formulations were better represented by the Hixson-Crowell model, while formulations containing a higher concentration of the mucilage were represented by the Korsmeyer-Peppas model. Nonetheless, five formulations showed a longer release than the reference HPMC formulation. More desirable results were obtained with a higher concentration of the mucilage (13-18%) and a lower concentration of metformin (40%).

Nodules on the Anterior Neck Following Poly-L-lactic Acid Injection.

Poly-L-lactic acid (PLLA) is a synthetic biologic polymer that is suspended in solution and can be injected for soft-tissue augmentation. The most common adverse events generally are transient in nature, such as swelling, tenderness, pain, bruising, and bleeding. Persistent adverse events of PLLA primarily are papule and nodule formation. Injecting PLLA into the anterior neck is an off-label procedure and may cause a higher incidence of nodule formation.

Comparison of biodegradable and durable polymer drug-eluting stents in acute coronary syndrome: a meta-analysis.

OBJECTIVE: To compare the safety and effectiveness between biodegradable polymer drug-eluting stents (BP-DES) and durable polymer drug-eluting stents (DP-DES) in patients with acute coronary syndrome (ACS). DESIGN: Meta-analysis of randomised controlled trials (RCTs). PRIMARY AND SECONDARY OUTCOME MEASURES: Major adverse cardiovascular events (MACEs) were considered the primary endpoint. Efficacy endpoints included target vessel revascularisation (TVR) and target lesion revascularisation (TLR). Safety endpoints included all-cause death, cardiac death, target vessel myocardial infarction and stent thrombosis (ST). METHODS: We searched PubMed, Medline, Embase and the Cochrane Controlled Register of Trials for comparative studies of BP-DES and DP-DES in patients with ACS from January 2000 to July 2021. Statistical pooling was performed to estimate incidence using a random-effects model with generic inverse-variance weighting. Risk estimates were computed with 95% CIs. RESULTS: Eight articles with seven RCTs that compared BP-DES and DP-DES in patients with ACS were identified and included in the qualitative and quantitative analyses. There was no difference in the baseline characteristics, except for the number of smoking patients (OR: 1.13, 95% CI 1.03 to 1.24; p=0.008, I2=29%), which was significantly lower in the BP-DES group. The meta-analysis demonstrated that MACEs, efficacy endpoints and safety endpoints were similar between the groups at 1 year. However, the incidence of total ST was significantly different between the BP-DES and DP-DES groups in the follow-up period (p=0.0001). Further analysis showed a statistically significant difference in MACEs (OR: 0.71, 95% CI 0.57 to 0.88; p=0.002, I2=0 %), TLR (OR: 0.71, 95% CI 0.51 to 1.01; p=0.05, I2=0%), TVR (OR: 0.70, 95% CI 0.52 to 0.94; p=0.002, I2=15%), total ST incidence (OR: 0.59, 95% CI 0.46 to 0.77; p=0.0001, I2=48%) and ST incidence (OR: 0.63, 95% CI 0.47 to 0.85; p=0.002, I2=0%) over 2 years. CONCLUSION: This meta-analysis revealed that both stent types demonstrated excellent safety and efficacy profiles at 12 months. However, a slight increase in MACEs, TLR, TVR and ST incidence was observed in the DP-DES group over the 2-year follow-up period, suggesting that BP-DES may be more favourable when treating patients with ACS. TRIAL REGISTRATION NUMBER: NCT00389220.

Hypersensitivity Reaction to Carbon Fiber-Polyetheretherketone Composite Spinal Implant: A Case Report.

CASE: A 52-year-old woman presented with localized hypersensitivity symptoms immediately after insertion of a carbon fiber-polyetheretherketone (CF-PEEK) vertebral fusion device. After a modified cutaneous patch test confirmed an allergic reaction to the implant, the device was surgically removed. The patient's symptoms were largely resolved 1 month after the removal of the device. CONCLUSION: CF-PEEK is a commonly used biomaterial in surgical implants. As far as we know, this is the first reported case of a hypersensitivity reaction to CF-PEEK.

Cutaneous hydrophilic polymer emboli following endovascular repair of an abdominal aortic aneurysm: a case and review of literature.

Hydrophilic polymer embolism (HPE) is a rare iatrogenic complication of the use of polymer-coated intravascular devices, which may affect several organ systems including the skin. Herein, we present a patient who developed a cutaneous eruption with associated neurologic manifestations secondary to localized HPE. This is a potentially underdiagnosed, life-threatening complication and physicians should consider HPE when evaluating skin eruptions in patients who have undergone endovascular procedures.

Safety and Efficacy of Patiromer in Hyperkalemic Patients with CKD: A Pooled Analysis of Three Randomized Trials.

Background: Hyperkalemia is a common electrolyte abnormality in patients with CKD, which is associated with worse outcomes and limits use of renin-angiotensin-aldosterone system inhibitors (RAASi). This post hoc subgroup analysis of three clinical trials evaluated the efficacy and safety of the sodium-free, potassium-binding polymer, patiromer, for the treatment of hyperkalemia in adults with nondialysis CKD. Methods: Data from the 4-week treatment periods of AMETHYST-DN, OPAL-HK, and TOURMALINE studies were combined. Patients had baseline diagnosis of CKD, hyperkalemia (serum potassium >5.0 mEq/L), and received patiromer 8.4-33.6 g/day. Patients were stratified by baseline eGFR into two subgroups: severe/end-stage CKD (stage 3b-5; eGFR <45 ml/min per 1.73 m2) and mild/moderate CKD (stage 1-3a; eGFR ≥45 ml/min per 1.73 m2). Efficacy was assessed by the change in serum potassium (mean±SE) from baseline to week 4. Safety assessments included incidence and severity of adverse events (AEs). Results: Efficacy analyses (n=626; 62% male, mean age 66 years) included 417 (67%) patients with severe/end-stage CKD and 209 (33%) with mild/moderate CKD. Most patients were receiving RAASi therapy at baseline (severe/end-stage CKD 92%; mild/moderate CKD 98%). The mean±SE change in serum potassium (baseline to week 4) was -0.84±0.03 in the severe/end-stage CKD subgroup, and -0.60±0.04 mEq/L in the mild/moderate CKD subgroup. AEs were reported for 40% and 27% patients in the severe/end-stage and mild/moderate CKD subgroups, respectively, with 16% and 12% reporting AEs considered related to patiromer. The most frequent AEs were mild-to-moderate constipation (8% and 3%) and diarrhea (4% and 2%). AEs leading to patiromer discontinuation occurred in 6% and 2% of patients with severe/end-stage CKD, and mild/moderate CKD, respectively. Conclusions: Patiromer was effective for treatment of hyperkalemia and well tolerated in patients across stages of CKD, most of whom were receiving guideline-recommended RAASi therapy.

Low fermentable oligosaccharides, disaccharides, monosaccharides, and polyols diet versus traditional dietary advice for functional dyspepsia: a randomized controlled trial.

BACKGROUND AND AIM: Prospective trials evaluating efficacy of specific diet restriction in functional dyspepsia (FD) are scarce. We aimed to assess efficacy of low fermentable oligosaccharides, disaccharides, monosaccharides, and polyols (FODMAP) diet in FD, compared with traditional dietary advice (TDA). METHODS: In this prospective, single-blind trial, patients with FD (Rome IV) were randomized into low FODMAP diet (LFD) and TDA groups, for 4 weeks (phase I). In phase II (4-12 weeks), LFD group was advised systematic re-introduction of FODMAPs. Symptom severity and quality of life were assessed using "Short-Form Nepean Dyspepsia Index (SF-NDI)." Primary outcome was symptomatic response (symptom score reduction of ≥ 50%), at 4 weeks. Study was registered with CTRI (2019/06/019852). RESULTS: Of 184 patients screened, 105 were randomized to LFD (n = 54) and TDA (n = 51) groups. At 4 weeks, both groups showed significant reduction in SF-NDI symptom scores compared with baseline, with no significant difference in inter-group response rates [LFD: 66.7% (36/54); TDA: 56.9% (29/51); P = 0.32]. On sub-group analysis, patients with postprandial distress syndrome or bloating had significantly better symptomatic response with LFD (P = 0.04). SF-NDI quality of life scores improved significantly in both groups. On multivariate analysis, factors predicting response to LFD were bloating and male gender. Incidences of adverse events (minor) were similar in both groups. CONCLUSIONS: In patients with FD, LFD and TDA lead to significant symptomatic and quality of life improvement. Patients with postprandial distress syndrome or bloating respond significantly better to LFD. Therefore, dietary advice for FD should be individualized according to FD subtype.

Biosafety of a novel covered self-expandable metal stent coated with poly(2-methoxyethyl acrylate) in vivo.

Covered self-expandable metal stents (CSEMS) are often used for palliative endoscopic biliary drainage; however, the unobstructed period is limited because of sludge occlusion. The present study aimed to evaluate the biosafety of a novel poly(2-methoxyethyl acrylate)-coated CSEMS (PMEA-CSEMS) for sludge resistance and examine its biosafety in vivo. Using endoscopic retrograde cholangiopancreatography, we placed the PMEA-CSEMS into six normal porcine bile ducts and conventional CSEMS into three normal porcine bile ducts. We performed serological examination and undecalcified histological analysis at 1, 3, and 6 months during follow-up. In the bile ducts with PMEA-CSEMS or conventional CSEMS, we observed no increase in liver enzyme or inflammatory marker levels in the serological investigations and mild fibrosis but no inflammatory response in the histopathological analyses. Thus, we demonstrated the biosafety of PMEA-CSEMS in vivo.

Toxicity risks of occupational exposure in 3D printing and bioprinting industries: A systematic review.

3-Dimensional (3D) printing and bioprinting are the new technologies. In 3D printing, synthetic polymers such as acrylonitrile, butadiene, and styrene, polylactic acid, nylon, and some metals are used as feedstocks. During 3D printing, volatile organic compounds (VOCs) and nanoparticles can be released. In the bioprinting process, natural polymers are most commonly used. All of these materials have direct and indirect toxic effects in exposed people. Therefore, the aim of this study was to provide a comprehensive review of toxicity risks due to occupational exposure to pollutants in the 3D printing and bioprinting industries. The Cochrane review method was used as a guideline for systematic review. Articles were searched in the databases including PubMed, Scopus, Web of Science, and Google Scholar. This systematic review showed that VOCs and ultra-fine particles are often released in fused deposition modeling and selective laser sintering, respectively. Asthma, chronic obstructive pulmonary disease, allergic rhinitis, and DNA damage were observed in occupational exposure to synthetic polymers. Metal nanoparticles can induce adverse health effects on the respiratory and nervous systems. This study emphasized the need to further study the toxicity of 3D printing and bioprinting-induced air pollutants. Also, consideration of safety and health principles is necessary in 3D printing and bioprinting workplaces.

The role of lignin and lignin-based materials in sustainable construction - A comprehensive review.

The construction industry in the 21st century faces numerous global challenges associated with growing concerns for the environment. Therefore, this review focuses on the role of lignin and its derivatives in sustainable construction. Lignin's properties are defined in terms of their structure/property relationships and how structural differences arising from lignin extraction methods influence its application within the construction sector. Lignin and lignin composites allow the partial replacement of petroleum products, making the final materials and the entire construction sector more sustainable. The latest technological developments associated with cement composites, rigid polyurethane foams, paints and coatings, phenolic or epoxy resins, and bitumen replacements are discussed in terms of key engineering parameters. The application of life cycle assessment in construction, which is important from the point of view of estimating the environmental impact of various solutions and materials, is also discussed.

Better response to low FODMAP diet in disorders of gut-brain interaction patients with pronounced hydrogen response to a nutrient challenge test.

BACKGROUND AND AIM: Previous studies have shown a reduction of gastrointestinal symptoms in irritable bowel syndrome (IBS) patients following a low FODMAP diet (LFD). It remains unknown which disorders of gut-brain interaction (DGBI) patients would benefit most from LFD. We aimed to analyze LFD response regarding a preceding nutrient challenge test (NCT). METHODS: Data of 110 consecutive DGBI patients undergoing NCT and LFD between August 2015 and August 2018 were analyzed retrospectively. LFD response was assessed by changes in IBS Symptom Severity Score (IBS-SSS). In mixed-effects linear regression models, the impact of hydrogen values and abdominal symptoms during NCT, performed with 30-g lactulose and 400-mL liquid test meal, on IBS-SSS changes were analyzed. RESULTS: Low FODMAP diet induced a significant IBS-SSS reduction of 78 points (95% confidence interval [CI] 50-96; P < 0.001). Patients with higher NCT-induced hydrogen increase during proximal intestinal transit had a significantly better LFD response (-66 IBS-SSS reduction per 10-ppm hydrogen increase, 95% CI -129 to -4, P = 0.045). Additionally, the higher the NCT-induced maximum hydrogen increase during mid-distal and distal intestinal transit, the better are the responses to LFD (-6 IBS-SSS per 10-ppm maximum delta hydrogen, 95% CI -11 to -1, P = 0.040). There was no association of LFD response with abdominal symptom generation during NCT. CONCLUSIONS: Our study is the first one analyzing and demonstrating significant associations between NCT results and LFD response. These findings are of high clinical importance, as they identify a subgroup of DGBI patients that may profit most from a restrictive LFD as first-line therapy.

Hydrophilic polymer embolization as an iatrogenic complication of endovascular interventions - a new entity.

Iatrogenic hydrophilic polymer embolization (HPE) is an underrecognised complication of endovascular procedures. In certain instances, HPE and related complications may lead to patiens death. Incidence of this phenomenon is not known. We evaluated retrospectively all autopsies of patients with a history of endovascular intervention performed by one pathology resident during a period of 8 months. There were 10 cases, which were examined histochemically and in polarized light.  We detected HPE in 2 of the 10 cases. In both cases the involved organ were lungs. Hydrophilic polymer embolization is a potential and easy-to-miss complication of endovascular procedures. It must be considered during histological examination of autoptic material.

Hydrophilic polymer embolization following flow diversion of cerebral aneurysms.

Foreign body embolization is a rare and potentially under-recognized complication of neuroendovascular procedures. This complication should be considered in the differential diagnosis for clinical or radiological deterioration following neurovascular interventions. We report a case of foreign body hydrophilic coating embolization that occurred following an attempted flow diversion of an intracranial aneurysm with dramatic flare-up after repeat exposure. We also provide a literature review of all reported cases of hydrophilic polymer embolization following flow diversion procedures.